I am looking for feedback on USB sound cards for someone who is ONLY interested in music playback and wants to hook up to a 2 channel analogue amplifier that is 40-50' away.

I am particularly interested in the Extigy (£122) and the Abit UA10 (£44) see here . I am aware of the Stereo-Link but here in the UK it gets expensive when you have to import it and getting it repaired or replaced might have it's problems.

I have read good and bad things about the Creative Extigy, but I think there are 3 things about this device that lead to confusion.
1. Creative market this device to laptop owners and people who don't want to open their PC up. There is an expectation that you just plug it in and use it and this leads to people having problems.
2. The device is now a bit more mature and there should be better driver support. I certainly have read that the new drivers have helped people.
3. Too many people appear to consider the Extigy an evil Audigy in a box. There are a lot of common features and components, however when you look at the cost vs features it scores well.

So my questions relate to someone using the latest drivers, running XP, with very low utilization of the total USB bandwidth, +1GHz PC, lots of Ram and again to stress, just wants to play music. I.e. recording, Midi and Games are not or any interest.

I have also read about the upsampling issues with Creative cards. However, is this going to provide any sound degradation that can be "heard"? Or is this an issue that has no noticable effect for music playback (only)?

One of the big evils of the Audigy is how it behaves on the PCI bus. Since the Extigy is USB, that is no longer an issue. However, during playback more CPU power is required to run it, and when playing games that usage goes way up. Since you're not going to be playing games with it (or even sitting in front of it when it's playing music), that is also no longer an issue.

I have no idea what Abit's technical support department is like, nor do I know how often they update drivers (or if XP just sees it as a "6-channel USB audio device" and installs its own set--I really don't know). Creative is probably a better bet here, since they just recently went back and re-wrote all their drivers in a unified manner in an effort to clear up some of the problems they were having.

There's a very good chance that the Abit device operates using a trio of 48kHz AC'97-type devices, as a lot of them are designed for low-power USB applications. That means it probably resamples. Most of the less expensive devices do since the target market wants 100% seamless compatibility with whatever they play back, without funky pops or clicks (when changing DAC clock rates) or error messages.

I can't really hear a difference (or at least anything bad) when listening to normal music that has been resampled to 48kHz. However, sine sweeps do reveal some terrible artifacts. My personal opinion is that even if I can't hear a difference then it's still better to err on the side of caution.

In any case, there is a SSRC software resampling output plugin for Winamp that will use the CPU to upsample and produce a much better quality 48kHz output than just about every other resampling method.

In my opinion you'd still do better if you bought a good quality soundcard, such as the M-Audio Audiophile or Terratec EWX 24/96, much better than the Extigy or the Edirol (I assume, don't know much about the Edirol), and hook it to your amp using a good quality well shielded cable, that doesn't need to be expensive.

I've tried a similar setup with a 15 m cable, and noticed no background hiss or hum.

Pros: simpler solution, I'd say cheaper too, less CPU hog compared to USB devices, better quality, good quality analog and digital inputs and outputs, good driver support in the case of the Audiophile.

However, I don't know if the difference on quality compared to the Extigy would be easily noticeable.

I had not heard of Edirol and on checking them out came across this interesting device - UA-1A USB Audio Interface Cable. I'm not sure if this is a "sound card" but it may be what I am looking for.

I am aware that using a good soundcard and shielded cable will get me to where I want to be. However, there are other factors that make the USB route very attracrtive. The rear of my PC is a real rats nest of cables, home network setup, cable TV point, 5 phone lines, etc. I would also like to use a portable USB card for outside party's using a laptop in the future.

Yeah, this may do the job. 2 things that are concerning me are the lack of information from Edirol on their site and also references to some USB devices that may not work. I was told by Edirol that the standard XP USB Sound driver is used but they weren't sure if there was any mixer control within this XP driver. They also said there was no resampling.

Some of their other professional USB audio devices have a listing of what will and won't work. They will only work with Intel or Lucent chipsets. No VIA or OPTi. I hope that doesn't apply to the UA-1A as well.

On the other hand the main .com site gives a list of compatible devices. I always worry when the list of incompatible devices is longer that the compatible ones. Anyway, I have a SiS7001 device which makes it incompatible straight off the MB. I would think that I could use an approved hub.

they make several usb > audio options and arent all that expensive. They have both analog and digital (optical) links, 2 of which are expressly designed with minidisc recording in mind, but one of which is meant as a hi-fi link.

Watch your USB cable length - you need something to regenerate the signal every 5m (you can buy a self powered hub or special active extension cables). This isn't a big problem but it adds to the cost.

Also, XPs handling of USB audio seems pretty rubbish.
I ran my USB apple soundsticks on 2000 server for months - they never missed a beat.
Then I upgraded to XP Pro ... Initially the soundsticks were unusably bad if I tried to do anything else on the PC while listening to music - but after installing every Microsoft hotfix known to man along with the dodgy VIA patch, it doesn't skip and pop all the time, just when I'm burning CDs.

From what I have found out, USB sound cards seem to work well if you make sure that the USB device on your motherboard or hub card, are compatible with the USB sound card. I notice that Edirol sell a recommended 4 port hub card should there be a compatibility problem.

Care needs to be taken to use quality USB cable and to use repeaters if you need to go beyond 5m. I can't define quality here but you may not really know if it will work until you hook the whole thing together.

If the 44 to 48KHz resampling thing bothers you, then there are plenty of USB devices arround. Otherwise, the Extigy is one of the best featured devices out there and appears to be stable and working very well with the latest drivers and firmware updates.

Also running other USB peripherals at the same time can cause audio break up if the task is USB intensive. A USB mouse and KB is OK but video or other intensive applications may cause problems.

I have just ordered a USB device from Autiotrak called an Optoplay with 2 x 5m USB repeater cables and a USB 2.0 PCI card (to use in 1.1 mode) and will report back with the results.